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Brief thermo-nociceptive stimuli elicit low-frequency phase-locked local field potentials (LFPs) and high-frequency gamma-band oscillations (GBOs) in the human insula. Although neither of these responses constitute a direct correlate of pain perception, previous findings suggest that insular GBOs may be strongly related to the activation of the spinothalamic system and/or to the conveyance of thermal information. To disentangle these different features of the stimulation, we recorded intracerebral electroencephalographic activity from 7 epileptic patients (9 depth electrodes, 58 insular contacts) and compared responses to brief stimuli from 4 modalities (painful thermo-nociceptive stimuli; non-painful cool stimuli; non-painful mechano-nociceptive stimuli; innocuous vibrotactile stimuli). All four types of stimuli elicited consistent low-frequency phase-locked LFPs throughout the insula, largely explained by a contribution of supramodal activity. The latencies of thermo-nociceptive and cool low-frequency phase-locked LFPs were shorter in the posterior insula compared to the anterior insula, suggesting a common processing of thermal stimuli – regardless of painfulness and nociception – initiating in the posterior insula. However, only thermo-nociceptive stimuli elicited an enhancement of insular GBOs, suggesting that these activities are not simply related to the activation of the spinothalamic system or to the conveyance of thermal information, but are preferential for thermo-nociception.